The mergers required to assemble large galaxies over cosmic time inevitably lead to the formation of a gravitationally bound pair of SMBH (a binary SMBH) at the centers of many galaxies. During the coalesce of a binary SMBH , gravitational radiation is emitted anisotropically with the result that a recoil (‘kick’) velocity is imparted to the merged SMBH. Recent advances in numerical relativity, have shown that in the case of spinning black holes, recoil velocities can be sufficiently large that they could cause the displacement of the SMBH from the center of its host galaxy, or in extreme cases, eject it entirely. Gravitational recoil might then be detected observationally, as an Active Galactic Nucleus (AGN) displaced from the center of its host galaxy , or via Doppler shifting of emission lines from the retained gas. Observational detection of high velocity gravitational recoil events would both confirm the results of numerical relativity and also have important implications for theories of galaxy evolution. To date, however, only two plausible gravitational recoil candidates have been reported and both are open to alternative interpretations. We start by reviewing the efforts to date to detect both radial velocity and spatial displaced AGN. We then present spectropolarimetric observations of two nearby AGN E1821+643 & , which reveal two new candidates, with the unique feature that Doppler shifts corresponding to the recoil velocity are observed in both direct and scattered (polarized) light.